For the most part, the narrator is angry with her husband because he treats her like a child. The husband's belief that his wife needs "rest" because of "nerves" angers the wife in a couple of ways. The first is that such an attitude denies that there is something fundamentally wrong with the wife. She believes that there is something that is not right with her mind and such a condition requires a form of gravity and seriousness that goes beyond the idea that "rest" is all that's needed. The husband's attitude feeds the larger issue of a paternalism that refuses to acknowledge his wife's voice. When she wants to go outside or write in a journal, the husband rejects these, stressing that the wife is not to any of these. The denial of voice, deliberate or unintentional, that the husband demonstrates to the wife is reason enough for her anger towards him.